Electronic tax calculation circuit for use in business accounting system



Dec. 27, 1966 R. TOWNSEND ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUS INESS ACCOUNT ING SYSTEM Filed Sept. 29, 1964 12 Sheets5heet 1 CLEAR IOx BEER BEER CLEAR SM. LG.

N $9 90 9 9x SAEE HOT $8 so a 6x CHOG A cHoC FR. $7 70 7 7x MILK FR 8 $6 60 6 6x GOFF. C

COKE COKE 5 50 5 5x SHAK SM 0 LAsT ORNG ORNG. 4 4o 4 4x ITEM g CLEAR CHSE SPEC. $3 30 3 3x BGR.

MULT

HE R TAX 20 $2 20 2 RESET 6 SUB $|0 I I0 I TEA TOTAL AMOUFF MuLT TOTAL CHANGE ENTRY T ON TOTAL TRANS.

CHANGE F I G I DISPENSER REMOTE READOUT PRINTER EMERGENCY POWER SUPPLY INVENTOR RALPH TOWNSEND REMOTE MACHINES ATTORNEY Dec. 27, 1966 R. TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed Sept. 29, 1964 12 Sheets-Sheet 2 F I G. 3

A64 :j COMPLETE ENABLE +CARRY L-CARRY TOTAL CENTS REGISTER 8+ FIG. 4A iSTAGE 5 3E VOLTAGE AT POINT 5+ I s| OPEN @H VOLTAGE U R2 AT POINT A FIG 48 RI B MI V V V l A-PRICE l B-PR|CE SELECT PIN SELECT PIN 0 (9 INVFNTOR 5| {:1} s2 RALPH TOWNSEND A-lTEM KEY B-ITEM KEY} BY 1 ATTORN EY Dec. 27, 1966 R. TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed Sept. 29, 1964 12 Sheets-Sheet 5 *ENABLE sET CIRCUIT INVENTORY COUNTER MvI USTEP A REGISTER 7 50 M sEc ITEMLINE ONE SHOT SET INPUT ITEM REGISTER KEY MULT'PUER FL (TRAILING EDGE) GATE vg Mv3 A MAz 3 M sEc SOMSEC ONE SHOT I ONE SHOT M62 INHIBIT MULTIPLIER KEYS FIG. 5 I

RESET/ MULTIPLIER I I MvI sTART GEN. I I v I l A REGISTER I (REST) PT I P SET INPUT u 3 MsEc [F M62 MULTIPLIER H H GATE I m ..E f 'l COUNT I COUNT 2 COUNT 3 ITEM LINE i i i "0" STAGE MULTIPLIER L RcI INVENTOR RALPH TOWNSEND ATTORNEY Dec. 27, 1966 R. TOWNSEND ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN Filed Sept. 29, 1964 FIG. 7

BUS INESS ACCOUNTING SYSTEM 12 Sheets-Sheet 4 couNTER DRIVER AMP.

CDA 2 CENTS COUNT A 1: ENABLE MECH CARRY GATEs Gm 1 w MEG COUNTER cARRY DRIVER AMP MC RESET f SET rfi ENABLE CARRY GATE sIGNAL A s A ENABLE E g COUNT 3 (I) 5 "2 g E I o MECHANICAL ACCUMULATOR MA 5w ONE ENABLE TRIGGER l SHOT 5KC,500-,40- R535 L R3 oscILLAToR I z; Bl I 05 sTAN0AR0- STANDARD T3 BINARY BINARY LF osG.I20-I 04 H 05" T2 D3 2 TI 82 [8 T ONE @Ieo' 080. L SHOT I80 PHASE ENABLE TRIG. GATE sIGNAL 2 \MV4 GATE sIGNAL 3 INVENTOR RALPH TOWNSEND ATTORNEY Dec. 27, 1966 Filed Sept. 29, 1964 R. TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM 12 Sheets-Sheet 5 FIG. 9

FIG. IO

0 OR |80 SAMPLE MAIN lN PHASE OSCILLATOR PHASE ENABLE TRIGGER 0 SAMPLE |80 SAMPLE 0' PHASE I80 PHASE ENABLE TRIG. ENABLE TRIG.

0 PHASE ml (|80 PHASE SELECT SELECT INVENTOR RALPH TOWNSEND ATTORNEY Dec. 27, 1966 R. TOWNSEND ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM 12 Sheets-Sheet 6 Filed Sept. 29, 1964 m: mmhwamm .rDmZ

INVENTOR RALPH TOWNSEND ATTORNEY m2: ww sa Im 00 OmO Dec. 27, 1966 R. TOWNSEND ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM 12 Sheets-Sheet 7 Filed Sept. 29, 1964 mwza wmod Emmi mx 44km; mmumzdmh m0 mwtamn wmOJo mmldmc zumo INVENTOR RALPH TOW NSEND $2 39. 45353 zo 5; m3. ikznmam ATTORN EY 6 R. TOWNSEND Dec ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN ESS ACCOUNTING SYSTEM BUSIN 12 Sheets-Sheet 8 Filed Sept. 29, 1964 H6. BA

PLUGBOARD APB IO DOLLARS DOLLARS TEN CENTS CENTS 3 z mumllllm TO INVENTORY COUNTER (0PT.)

8 R s S Y AS R T8 3% A Y Y Y T UR LE LE EE NE M K K K K ME D2 mm 0w W 0 I MVI 50 M SEC.

PULSE GENERATOR INVENTOR RALPH TOWNSEND ATTORNEY DELAY GEN.

MULTIPLIER GATE 3 M SEC DELAY GEN.

INHIBIT m wmmm mmmm MULT- RES Dec. 27, 1966 R. TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed- Sept. 29, 1964 12 Sheets-Sheet 9 TO PRINT WHEELS INDICATOR IO DOLLARS INDICATOR DOL LARS INDICATOR IO CENTS INDICATOR CENTS VISUAL INDICATOR INPUT REGISTER IR INPUT TO TOTAL COMPLETE ENABLE INPUT CARRY GATE OSC.

ADD INPUT TO TOTAL FIG. I38 RALP'E T BIIEEND ATTORNEY Dec. 27, 1966 R. TOWNSEND 3,

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed Sept. 29, 1964 12 Sheets-$heet 1O BINARY I DIRECTIONAL RING COUNTER 7O MSEC.

DELAY A65 TO AG I? TOTAL REGISTER TR F I INVENTOR RALPH TOWNSEND ATTORNEY Dec. 27, 1966 R. TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed Sept. 29, 1964 12 Sheets-Sheet ll 'DIRECTIONAL RING COUNTER ZOO USEO.

DELAY sno R03 FF FFA OPEN DRAWER E6 M AN SALE TOTAL SPECIAL.

E SUB-TOTAL INVENTOR RALPH T OWNSEN D TRANSACTION COUNTER ATTORNEY Dec. 27, 1966 TOWNSEND 3,294,960

ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Filed Sept. 29. 1964 12 Sheets-Sheet 12 FIG. IG. I3A FIG. I38 FIG. I30 FIG. I30 FIG. |3E

FIG. |3E

COMMAND COMPLETE COUNTER COUNTER DRIVER D E AMP AME OSCILLATOR D CENTS ENABLE CIRCUIT D MECHANICAL SRD ACCUMULATOR MA DRAWER OPEN DRAWER CLOSED x 5C E E E1 TOTAL (SYSTEM CLEAR) TRANSFER CHANGE CLEAR INVENTOR RALPH TOWNSEN D ATTORNEY United States Patent C 3,294,960 ELECTRONIC TAX CALCULATION CIRCUIT FOR USE IN BUSINESS ACCOUNTING SYSTEM Ralph Townsend, Darien, Conrn, assignor to American Machine & Foundry Company, a corporation of New Jersey Filed Sept. 29, 1964,8121. No. 400,067 12 Claims. (Cl. 235160) This invention relates to business accounting systems and machines, and particularly to such systems and machines for providing automatic price and tax computation, indication and storage, and other related accounting operations on, or records of, numerical data occurring in connection with the sale of items or services in limited item business establishments.

An object of the invention is to provide such automatic accounting operations quickly, accurately and economically with the use of a comparatively small amount of apparatus with simple solid state circuitry.

Another object is to provide in one machine certain basic accounting operations on numerical data in connection with the sale of different items or services on separate orders, and to enable the machine to be adapted readily to provide one or more other related accounting operations depending on special requirements encountered.

Other objects are to electronically compute the item and total prices and the tax thereon in connection with a sale of a number of items or services; to provide automatic visual indication of the computed prices to the operator and customer; to control the preparation of a bill with item and order prices; to electronically calculate the change from the amount tendered in payment of a bill; to produce accumulative records of the amount of sales, taxes and the number of items sold or dispensed over a given time period; and to provide automatically inventory and other business controls, including the control of the operation of a cash drawer in an accounting machine, the control of auxiliary machines or indicators and the resetting of the electronic control circuits for the machine to their initial operating condition after their operation.

These objects are attained in accordance with the invention by a system or machine for limited item use, in place of the usual cash register, which includes in a suitable console or container a basic unit for providing selected control operations, including computation of item and order prices, in connection with the sale of items or services; and provisions for readily changing this basic unit to include one or more different optional control features to meet the environmental needs of the machine. All of the control operations utilize solid state electronic circuitry throughout with their inherent advantage of known reliability which is mandatory in online operations of this type.

In accordance with the invention, some major considerations are minimal storage capacity requirements of the electronic control circuits and elimination of complexity by utilizing the inherent speed of the electronic circuitry, both of which contribute to cost reduction. Probably, an important advantage of the novel machine is its design flexibility. Printed circuit cards can be changed or the wiring modified with relative ease to facilitate adding optional features and connecting additional units thereto, such as a keyboard with preselected items, or an associated printer for automatic rapid bill mg.

A distinguishing feature of this machine is the provision of an item keyboard comprising a number of suitably-labeled service or item keying means or push but- 3,294,960 Patented Dec. 27, 1966 tons for controlling the electronic apparatus to enter the price of such a service or item, previously set up on an associated adjustable price board, into a total price by operation of the relevant key. Because all services or items do not have a fixed price, the item keyboard in the machine is supplemented by a manual amount keyboard of the standard adding machine type which can be used for direct parallel entry into the machine for special items.

In actual use of the machine, for example, several price lists may be set up each on an associated adjustable price board, of the printed circuit type with pre-set sliders or pins, which can be plugged into the machine or inserted into holders on the machine quickly and with ease. At the time of change, the individual descriptive labels on cards associated with the item or service keys on the keyboard may be changed accordingly, so that the operator need not consult a separate price list or remember any price except that of the special items entered through the amount keyboard.

As only a single bill is to be printed by an associated printer under control of the novel machine which is to be presented for payment, it is desirable to provide a record of the total cash received and the tax, if any, thereon. This is accomplished by the provision of two running total counters in the electronic equipment, which can be read at intervals and checked against the cash in the till.

In addition to the service or item and amount keys, the keyboard of the machine-contains a number of other functional keys, push buttons or control bars for controlling the electronic control units to provide the computing, calculation or storage functions. The basic machine also contains lighted display means for visually indicating computed prices, a cash drawer and a counter drawer containing the electronic control units.

The electronic controls include two bidirectional registers, which may be referred to as the Input Register and the Total Register, constituting a memory for the machine. Each register is composed of four bidirectional ring counters having a maximum capacity of $99.99 and operating under control of keys on the keyboard in the manner which may be briefly described as follows: Amounts may be entered into the Input Register by operating an item or service key which energizes a price matrix in the associated adjustable price board having a maximum capacity of $9.99, entering a pre-set amount, or directly by operation of an amount key and an amount entry key to selectively enter a price. Operation of either the item key or amount entry key causes the Input Register price information to be added to the Total Register, and at some later time the new information is entered into the Input Register. This sequence of events is controlled by shift register means which, in effect, is pre-programmed for the item entry operating cycle of the machine to be referred to later.

The machine also includes a number of unidirectional ring counters controlled by different functional keys to control item entry into the Input Register, computing a sub-total or sub-total plus tax and to calculate change.

A feaure of the electronic control means is that, in order to speed information transfer, the dollars and cents are operated upon by the ring counters separately and simultaneously. The maximum number of pulse to be transferred is 99, which takes approximately 20 milliseconds. In transferring information between the Input Register and Total Register, the bidirectional counters in the Input Regiser are counted down, and those in the Total Register are counted up by the amount that was in the Input Register. The carry pulses, which can occur when the Total Register cents counter passes 99 pulses, are stored in an electronic flip-flop and entered in the Total Register dol- 3 lars counter after both the dollars and cents Input Registers are at zero.

The optional features in the machine include additional item keys in modules of ten; a multiplier arrangement; an automatic tax computation circuit with an associated tax total counter; an automatic change calculating circuit; an emergency power supply; a transaction counter; separate mechanical data counters and an associated flip-flop control; and circuits for generating signals for controlling an external change dispenser, a printer, remote readout and other apparatus, such as inventory counters and remote machines for other purposes.

The optional multiplier arrangement is provided by a ring counter into which the number of each item purchased on each order and the total price thereof is set through a number of multiplier keys 3 to 10, in conjunction with operation of an item key. The optional inventory counters work in conjunction with the item keys and the multiplier keys, if used, to record the number of items ordered.

In the optional change calculation, the tendered amount is placed on the keyboard and the change calculated under control of a change key operating the ring counters so the amount of change is stored in the Input Register and is indicated on the price indicator.

The optional mechanical counters are used to accumulate such information as Total Sales, Individual Waiter Totals or Tax Totals. Because of the relatively slow speed of the mechanical counters (40 steps per second), the dollars and cents mechanical counters are operated simultaneously wherever possible, and any carries from the cents to the dollars counters are stored in an electronic flipflop and passed into the dollar accumulator at some time other than when the dollar counter is being stepped.

The above and other objects and features of the invention will be better understood from the following detailed description thereof when read in conjunction with the various figures of the accompanying drawings in which:

FIG. 1 is a pictorial view of the system of the invention including perspective outline views of the machine, and associated apparatus which are controlled by signals therefrom;

FIG. 2 is a top view of the keyboard in the machine of FIG. 1;

FIG. 3 is a block schematic of part of the register transfer block which is used for transferring price information from the Input to the Total Register;

FIG. 4 is a diagram of a portion of the circuit arrangement or adjustable price board for setting an item price into the Input Register of the electronic control circuits of the machine under control of an item key, and FIGS. 4A and 4B are curves used in connection with the description of operation of the arrangement of FIG. 4;

FIG. 5 is a block of the building blocks comprising the optional multiplier arrangement;

FIG. 6 is an illustration of timing waveform used during the multiplier cycle (for 3 items);

FIG. 7 is a black diagram of the mechanical accumulators and the carry flip-flop for accumulating Total Sales, Individual Waiter Totals, Tax Totals or other Total information in the system of the invention;

FIG. 8 is a circuit diagram of one type of selective oscillator which may be used for providing the various frequencies used in the optional automatic tax cycle and other electronic control circuits of the machine of FIG. 1;

FIG. 9 illustrates the selective oscillator waveforms provided by the oscillator of FIG. 8;

FIG. 10 is a circuit diagram of a selective gate sampler which may be used for sampling a gate in the system of invention;

FIG. 11 is a simplified block schematic of the circuit used for calculation of sales tax;

FIG. 12 is an operation flow chart of the machine of the invention;

FIGS. 13A to 13B are in combination, an overall schematic or logical diagram of the electronic circuits of a machine in accordance with the invention, including the optional features; and

FIG. 14 is a block diagram of the relative arrangement of FIGS. 13A to 13E.

FIG. 1 pictorially illustrates a system in accordance with the invention and includes an outline perspective view of the computing and calculating machine showing it external appearance. The machine, as shown, includes as components: a sloping keyboard; a cash drawer; a counter drawer which houses the electronic control equipment, and a visual price indicator which may be of the known NIXIE neon lighted display type, or other suitable visual display devices.

Also, attached to the back of the machine are conductors for transmitting the control signals stored in the elecronic circuits in the counter drawer for controlling the operation of an external automatic change dispenser; a 're= mote price readout, which also may be of the lighted dis play type; a printer for providing bills; and remote apparatus for inventory control and other purposes. For example, the controlled apparatus may include a menu item memory (MIM) device for controlling the operation of a food idspensing machine or automatic cooking apparatus and an associated inventory counter, such as disclosed in the co-pending patent application of William A. Hadley et al., Ser. No. 267,530, filed Mar. 25, 1962 (now abandoned). Also shown, are leads for connecting an emergency power supply, such as a battery through a plug=in socket (not shown) for use when the regular power ource fails. The machine may include other plug-in sockets (not shown) for connecting the other control apparatus to the machine.

As shown in FIG. 2, the keyboard of the machine includes up to 50 suitably-labeled item keys or push buttons; a plurality of amount keys or push buttons; and a plu rality of multiplier keys labeled 3 to 10. Also, the keyboard includes a number of functional keys including Amount Entry, Multiplier-Reset, Total Transfer, Sub- Total, Manual Tax, Special, No Sale, Clear and Change keys, Last Item Clear and Total bar, as shown. The keyboard may have provision, such as card holding clips (not shown), for facilitating changing the descriptive legends associated with the keys, and an adjustable price board or matrix which is attached to the keyboard in any suitable manner.

Register components The basic registers are made up of four bidirectional ring counters each, which preferably are of the electronic bidirectional type, such as disclosed in the patent of Marvin Felcheck, No. 3,248,562,, issued Apr. 26, 1966. As shown in FIGS. 3, 13B and 13C, the bidirectional ring counters are connected in pairs to provide a cents pair and a dollars pair in the Input Register and in the Total Register. Carries are connected within each cents pair and each dollars pair, but no carry is directly connected from the 10 counter to the unit dollars. Separate input lines may be provided for add and subtract on the unit cents and unit dollars counter.

Register Output Gating Murphy, Ser. No. 273,347, filed Apr. 12, 1963, under the-v sectional heading Output Gating in the specificationv and illustrated in FIG. 4 thereof.

Briefly, this technique involves placing a switch in series with the gate resistors through which current must flow to read out of the gates. When the series switch is.

5 open the gate cannot conduct current and is therefore disabled. This series switch is a transistor which is turned on and off as a function of the ring counter drive pulses. It is on at rest times and off during information transfer.

The principal features of the electronic circuit arrangements of the system or machine of the invention, the complete circuit schematic or logical diagram of which is shown in FIGS. 13A to E in combination to be described later, may best be described in connection with the simplified circuit and/or block diagrams of FIGS. 3 to 5, 7, 10 and 11, and FIGS. 6 and 9 illustrating the timing and oscillator waveforms used in connection with the description of operation of some of these features.

FIG. 3 illustrates in block schematic form a portion of the register transfer block used to transfer price information stored in the Input Register IR under control of the item keys on the keyboard of the machine through the associated adjustable price board APB. Each of the bidirectional ring counters in these registers has a decade configuration of to 9 positions or stages electronically equivalent to a bidirectional stepping switch indicated diagrammatically by the usual coaxial ring symbol. Each depression of an item key, for example, through the adjustable price board, will cause the transmission of a pulse to the ring counter and cause a stage to be energized. Of the ten output positions any one will store an output voltage at any time constituting a memory representing the price of the item ordered.

An AND gate AG3, which ANDs together the zero storage signals of ring counters 1R1 and 1R2 is enabled by an enabling pulse via OR gate 0G1. The enable signal is 180 out of phase with the output of the selective oscillator SO (FIG. 8) which drives the cents ring counter 1R1. The enable signal is a pulse, so, in effect, the ring counters gates are sampled.

Transfer of information from Input to Total Register (Add) As shown in FIG. 3, the Input Register includes a cents ring counter 1R1 and a 10 cents ring counter 1R2. It is assumed that 1R1 has been set to the No. position and 1R2 to the No. 2 position, corresponding to a price of 2.5 cents, under control of the item keys through the price board APB. The 25 cents is transferred out of the counter IR1 into the Total Register TR, which includes a cents ring counter TR and a ten cents ring counter TRZ, as well as a dollar and a dollar ring counter (not shown in this drawing), in the following manner:

In the reset condition, a flip-flop FFI is reset, and disables an AND gate AGI and enables AND gate AG3 via an OR gate 061. Since there is a number in the Input Register IR, the signals from IRl and IR2 to AG3 are zeros and the outputs of an amplifier A2 are also at the zero level. Therefore, an AND gate AG i is disabled and the AND gate AG2 is one-half enabled via an inverter I2 acting on the zero signal from amplifier A2.

To start the transfer cycle, the start signal, normally at its zero level, changes to one which acts to set the flip-flop FFl via AND gate AG2 and an amplifier A3, and causes gate AND A61 to be one-half enabled. The pulse oscillator SO (FIG. 8) connected to one input thereof now begins to pass its signal pulses through AGI and amplifier A1 to begin the counting down of the IRll and 1R2 counters in the Input Register. The signals in the output of AGI, which cause the counting down of the Input Register (the output of AGI), also acts to count up the Total Register counter (TRI) via an amplifier A4.

The AND gate AG3 is now being enabled via OR gate 0G1 by an enable signal of short duration at the same frequency as, but out of phase with, the oscillator signal. After 25 oscillator pulses have passed through AG2, 1R1 and 1R2 are at their respective zero stages or positions, and the enable pulse causes AND gate AG3 to emit a one pulse which resets flip-flop FFI via amplifier A2. AND gate AG is now disabled and the oscillator pulses can no longer cause a count in the Input and Total Registers. Since the start signal and the output of A2 are both at the one level, the AND gate AG4 passes a signal which indicates the cents transfer is complete.

The reason for the FFI enable signal to AG3 is now evident for, if it were not required, AGS would emit a series of one pulses at the enable frequency. Because of system considerations, only one D.C. level change is desirable to indicate the cents transfer is complete.

The information transfer from the Input Dollars Register to the Total Dollars Register of the machine of the invention is effected in a similar manner. Therefore, the Input Dollars and Cents Registers may transfer their information simultaneously to the respective Total Registers. It is necessary to AND together the Cents Complete and the Dollars Complete signals produced by AND gate AG4 and the similar AND gate in the dollar register and to use the resulting signal to indicate completion of Input to Total Register transfer, as shown in FIGS. 13A and 133.

The carry pulse which may ensue from the Total Cents Register in the event of a cents count passing through 99 is stored in a Total Carry flip-flop FF (shown in FIG. 13C) and gated into the Total Dollars Register at some later time.

In the event that the Input Register contains no information and a start signal occurs, a quick complete signal passes through AND gate AG4. This is accomplished via the output AND gate AG3 and the FFT enable signal being at one in the reset condition.

The same technique as described above is used in transferring price information from the Total Register to the Input Register. It will be referred to as either ADD from Input to Total Register or ADD from Total to Input Register (see Table I).

Setting the Input Register During the inserting of Item information into the machine, the previous information or item in the Input Register is shifted and added to the Total Register. At some later time, the item being entered into the machine is entered into the Input Register. The closure of an item key starts the A cycle (Table I) which is used for item entry. FIG. 4 shows how an item key determines which price is set into the Input Registers. Point (D) is the enable point for the fifth stage of a particular ring counter which could then correspond to either 5 or 50 cents, or 5 or 50 dollars, depending upon which of four ring counters in the Input Register is chosen. To preestablish the price associated with an item key, up to three pins are inserted in the price matrix of the associated adjustable price board. Each pin would choose a gate in one of three input ring counters. When the pin is inserted, points (D) and (E) are shorted thereby establishing a certain price (one digit of it) for that item key. After any item key is depressed a set pulse is inserted at point (C). If switch S1 is open, point (A) is held at B+ potential, reverse biasing diode D1. The set pulse passing through capacitor C1 being B-lin magnitude cannot overcome this reverse bias, and a signal never passes through D1 to set the fifth stage or position of the ring counter. If Si had been closed, then point (D) is clamped to ground via D2 and the voltage at point (A) goes B-|- volts below ground when the set pulse passes through C1. This forward biases D1 and passes a pulse to point (B). This negative pulse acts to activate the fifth stage or position of the ring counter. The voltage of point (A) with the switch S1 open or closed is shown by the curves of FIG. 4A and FIG. 4B, respectively. The diode D2 is an isolation diode, so that many items can have the same digit in their prices. When the manual entry input keyboard in the machine is used, no isolation aaeaaeo diode is necessary since a separate switch is used for each ring counter gate.

The Multiplier To facilitate the entry of a number of single items on each order, a multiplier is added as an option to the machine. The multiplier works in conjunction with the A cycle Register (Table I). The basic function of the A cycle is to enter items into the Input Register IR.

FIG. shows the building blocks comprising the multiplier and FIG. 6 shows the timing waveforms during the multiplier cycle. When it is desired to use the multiplier, one of the multiplier keys (3 to is depressed setting the ring counter, say, RC1, for the number of items desired (i.e., for 3 items, stage or position No. 3 of the counter is set). To start the cycle, the item key is depressed and held down until the completion of the cycle. (If the item key is lifted before the completion of the cycle, then depressing the item key again will complete the cycle with no errors in calculation). Referring to FIG. 5, when the item key is depressed the inventory counter IC (where this option is provided) for that item is stepped, the set circuits for the Input Register IR are enabled, AND gate MGI is one-half enabled, and multivibrator MV1 (50 msec., one-shot) is triggered via amplifier MAI. The normally Zero output of MV1 (zero: is high voltage) acts to step register A and the normally one output acts to inhibit AND gate MG1. The A-Register goes through its normal (Input to Total) transfer cycle. When MV1 concludes its 50 msec. active state it sets the Input Register and enables the other half of M61. The output of M61 triggers MV2 and steps RC1 one step back toward Zero. The output of MVZ inhibits MG2 for 3 msec. so that if RC1 is stepped back to zero the output of MA3 will then inhibit MG2 so that no pulse is sent to MV3. If RC1 is not stepped to zero, MV3 will be triggered after a 3 msec. delay. The output of MV3 (50 msec. positive pulse) acts through the closed item key exactly as if the item key had been opened for 50 msec. and then again depressed. The cycle again repeats until stopped by RC1 being stepped to zero and inhibiting MG2 via amplifier MA3.

The time delays of MV1 and MV3 are selected to be 50 msec. each so that the maximum speed of the inventory counters never exceeds 10 counts per second. For a multiplier cycle of 10 times, the time required is approximately 1 second.

Change calculation and mechanical total Because of the bidirectionality of the Input and Total Register, many operations become fairly simple, such as change calculation. To calculate change, the amount tendered by the customer is placed in the amount keyboard by depression of the necessary amount keys and the change key is then depressed. The bill or check total is placed in the Total Register TR and the amount tendered in the Input Register IR. Both registers are counted down simultaneously. When the Total Register TR is counted down to zero, the process is stopped and the amount remaining in the Input Register is the difference between the tendered amount and the check total, or the change.

As the Total Register TR is counted down (both dollars and cents simultaneously), the cash total in the mechanical accumulator MA to be described later is stepped up by the same amount. Any mechanical carry pulse is stored in the associated mechanical carry flip-flop device FF and passed into the dollar accumulator of the mechanical accumulators at a later time (see FIGS. 7 and 13A to 13E).

ical counters are provided to accumulate such information as Total Sales, Individual Waiter Totals or Tax Totals.

Because of the normally relatively slow speed of the mechanical counters, the mechanical dollars and cents counters are to be counted simultaneously wherever pos sible. Any carries from the cents to the dollars is stored in an electronic flip-flop and passed into the dollars at some time other than when the dollars counter is being stepped. FIG. 7 is a block diagram of the arrangement used to time share the counter drivers (so that only two are necessary in the machine), and to handle the cents carry pulse.

The counter driver amplifiers CDA and CDA each supply a fixed width, positive pulse, as a drive signal for the dollars and cents section A to C of the mechanical counters MC respectively driven thereby. The enable circuit (shown by box IE) functions as a switch which supplies a ground path for the counter drive coil of the counter amplifier. When a drive signal occurs, only those counters whose enable circuits have been activated "will be stepped.

To understand the circuit operation, assume that $950 is the amount to be entered in the A counters which presently contains the number 65 and the A dollars counter the number 15. The enable circuits E for both A counters are .activated. Pulses are fed into the cents and dollars counter driver amplifiers CDA and CDA simultaneously, 50 pulses into the cents amplifier and 9 pulses into the dollars amplifier. The A cents counter is stepped to 15 with a carry ensuing when the counter passes through 00. The mechanical carry flip-flop FF is set enabling one-half of the mechanical carry gates G The A dollars counter is stepped to 24. The count in the A counters is now $24.15 with the carry stored in the mechanical carry fiipflop FF An Enable Carry Gate signal now occurs which passes a single pulse through the carry gate G which adds one to the A dollars count. The final and correct count in the A counters is now $25.15. The reason for driving the dollars and cents counters simultaneously is to achieve time saving. If a single A counter with 4 or 5 digits was used, then 950 pulses would have to be added to the counter. With separate dollars and cents counters and simultaneous pulsing the time is determined by the 50 pulses passed into the cents counter.

The selective oscillator Because of the many functions and operations performed by the machine, several frequencies of operation are desirable and necessary for the various operations.

To obtain these various frequencies, the desirability of a single oscillator, each frequency of which can be selected by a gating signal as against several oscillators, is readily apparent. FIG. 8 shows one type of selective oscillator SO which may be used in the machine to obtain frequencies of 5 kc., 500 cycles, 40 cycles and 20 cycles. Also provided is the enable trigger pulse which is used to complement the oscillator 180 signal pulse in the automatic tax system. FIG. 9 shows the various wave-forms which can be produced by this selective oscillator.

The components of the selective oscillator and their connections will be described in the following description of its operation. Qll is a unijunction transistor to which the timing circuits R3C3, R4-C4 and RSCS are connected. With both transistors T2 and T3 in the unoperated condition, the capacitor C5 is charged from the associated direct current source B faster than either capacitor C3 or capacitor C4 because of its nearer location to that source. Therefore, Q1 fires repeatedly according to the time constant of RSCS. The signal produced by Q1 is amplified by transistor T1 and the amplified wave used to trigger the binary B1 causing it to give at (B) a square-wave output at one-half the R5C5 frequency, as shown by the uppermost curve of FIG. 9. The two outputs of the binary B1 are used to trigger the one-shot multivibrators MV3 and MV4, respectively, to produce outputs which are respectively out of phase. The (C) output from MV3 is used to trigger a second binary B2 which operates to produce at its output (E) a half frequency square wave (20 cycles). At output (C) of multivibrator MV3, the main oscillator output of frequencies kc., 500 cycles or 40 cycles is available; at the output (D) of multivibrator MV4, the out-of-phase 180 signal to the main oscillator; and at point (P) and (G), the respective complementary signals (see FIG. 9). The binaries B1 and B2 may be preferably of any of the standard electronic types.

To change the frequency, transistor T3 is turned on by a gating signal 3 shorting the capacitor C5. The RSCS timing combination is now isolated by diode D5, and the frequency is determined by timing circuit R4C4. If both T3 and T2 are turned on by other gate signals, respectively, the frequency is determined by timing circuit R3C3. As many frequencies as there are gating networks therefore can be obtained.

The selective gate sampler In the system of the invention, it is desirable to sample a gate at some time other than when the inputs are changing. Because of system requirements, the gates may be sampled in phase or out of phase with the main oscillator signal. One circuit for accomplishing such selective sampling is shown in FIG. 10. In this circuit, the transistors T5 and T7 are alternately turned on for 50 ,aseconds by the 0 phase and 180 phase enable trigger signal produced at point (C) and (D) of the selective oscillator of FIG. 8. If it is desired to have the 0 sample, transistor T4 is turned on and the 0 sample output occurs at both points (H) and (J). The 180 sample will occur at (K) and (I) when transistor T6 is turned on instead of T4. Diodes D6 and D7 allow isolation so that only (H) or (K) is active while (I) is active.

Tax calculation FIG. 11 shows a simplified version of the overall logical circuitry of the machine of the invention, which is concerned with the calculation of sales tax. In the description following, only the more important control apparatus will be specifically referred to by characters or numbers.

Referring to FIG. 11, T1111 and TRZ are the bidirectional cents and ten cents ring counters in the Total Register; similarly, TR3 and TR4 are the bidirectional one and ten dollar ring counters in the same register. The flip-flop FF11, controlled from the dollar ring counters TR3 and TR4 through AND gates AGZZ and AG23, changes state when the dollars counters reach $2 and remains in this state for higher dollars but reverts to its original state when counting down past $2. The flip-flop FFIZ controlled from the Total Register counts in binary in step with the dollars ring counters and indicates whether the amount therein is 0 or $1, and this also occurs when TR3 and TR4 are counting either in forward or reverse. Ring counter T controlled from the output of the ring counters in the Total Register, is a multi-step bidirectional counter which, as shown diagrammatically, is arranged by a feedback loop so that it counts up to two or three steps, for example, 0, 1, 0, 1, etc., or 0, 1, 2, 0, 1, 2, etc.

The input terminals of a group of multi-input AND gates AGS, AG6, AG17, respectively, representing different tax breaks under the tax laws of the particular region are respectively connected to bus wires in a wiring matrix WM by an appropriate pre-set wiring arrangement. This may be a printed circuit Wiring arrangement which can be plugged in to connect for the appropriate tax law, having several columns of parallel conductors with cents and 10 cents portions which are, in turn, connected to appropriate output connections of the cents and 10 cents ring counters TR1 and TR2. These gates (AGE to A617) fall into four groups which are controlled by enabling lines A, B, C and D, themselves by the connection shown controlled by the outputs of F1 11, F1 12 and T of which only one is active at one time. Thus,

10 line A is active when the dollars counters TR3 and TR4 contain $00., line B is active when TR3 and TR4 contain $01., line C is active when TR3 and TR4 contain $02., 04., 06., 08., 10., etc., and line D is active when TR3 and TR4 contain $03., 05., 07., 09., 11., 13., etc.

The value of the tax break depends upon the particular value of the connections to the ring counters TRl and TR2.

The outputs of the group of AND gates-A65, A66, AG7 are respectively connected to a different input of the OR gate 067 the single output of which is connected through other gating means and amplifiers to the tax line leading to the tax cents mechanical counters in the mechanical accumulator MA of the system, and to the cents bidirectional ring portions of the Input Register 1R.

The input terminals of four additional multi-input AND gates AG18, A619, AG20 and AG21, respectively,

representing different tax breaks in the dollar portion, are connected through other buses in the Wiring matrix WM to respectively different outputs of F1 11 and F1 12 and T The single outputs of the gates AGlS to AG21 are connected to different inputs of the OR gate 0G6 the output of which is connected through amplifiers and other gating means (068) through the flip-flop F1 13 and another AND gate A626 to the tax pulse line.

The functions of the unidirectional ring counter T other gating devices and the delay multivibrators controlling the operation of the elements of the tax calculating system described above will be brought out in the following detailed description of the operation of that systern in connection with a typical sale.

The first operation is to transfer the sub-total which is in the Input Register IR and being displayed in the visual indicator V1, to the Total Register TR in the manner which has been described in connection with FIG. 3. Referring to the Program (Table 1), the D counter steps from the D0 to the D1 portion of the D cycle in the operation of the machine, and the total amount standing at this time in the Input Register is transferred to the Total Register. At the same time that the dollars amount is transferred to TRE and TR4, FFII. is set if the amount exceeds $02.00, F1 12 is counting in binary and is set 0 or 1 respectively when the dollar amount is odd or even. T is also counting and in this case is also at 0 or I depending upon whether the dollar amount is odd or even. If, however, the tax laws had been such that the tax breaks repeated over a $3 cycle, T would have been 0 for $00.00, $03.00, $06.00, $09.00, etc.; 1 for $01.00, $04.00, $07.00, $10.00, etc.; and 2 for $02.00, $05.00, $08.00, $11.00, etc.

The Connecticut state sales tax will be used as an example. A portion of it is shown in the following table:

Sale Sale Tax Tax (Cents) (Cents) From To From To It shows that the cents part of the tax amount charged on sales follows a regular pattern above $2, and repeats itself at every even dollar; and below $2 the tax breaks do not follow a regular pattern. A study of the tax systems throughout the United States indicates that a similar pattern is followed in most of the states. Up to $1 or $2, the tax breaks are irregular; and above $2 the tax breaks follow a pattern which repeats itself every dollar, two dollars or in rare cases three dollars. 7

The flip-flop F1 11 indicates the change from irregular to regular breaks and flip-flop FFIZ indicates whether the amount is between and $1 or $1 and $2. The step ring counter T controls the repetitive cycle above $2 which may repeat over $1, $2, or $3 intervals depending on the state law being applied, and it is prewired accordingly. Preset wiring also controls the point at which FFll is set.

Assume the Connecticut sales tax is being calculated and that the total amount of the bill is $5.79, so that 79 is stored in TR1 and TR2, $5 in TR3 and zero in TR4. The flip-flop FF 11 is set to the 1 state via the left-hand gate A622 through A624 enabled by D3 (not D3) of the associated selective oscillator SO, because the amount is more than $2. The flip-flop FFIZ is set to the 1 state (odd dollars); and T is connected to count 0, l, O, 1, and is in the 1 state.

At completion of the transfer to the Total Register TR, the D counter of the Program (Table I) steps to D2. In this step, the total cents ring counters TR1 and TR2 in the Total Register are counted down to zero, and the contents (79;?) are transferred back to the Input Register cents counters. As the value in TR1 and TR2 passes through each break, in this case (5) .58, (5) .29, a tax gate selected by F1 11, FFIZ, and T is enabled sending a tax pulse through the large OR gate 067: (a) to the Input Register cents where it is added to the total (in between the pulses for the regular total being transferred back); and (b) to the tax cents total counter in the me- 'chanical accumulator MA. The speed of counting TR2 and TR1 is 500 c.p.s., so that tax pulses issue at approxirnately A of this speed, or about 17 c.p.s. which is compatible with the mechanical speed of the tax total counter.

When TR1 and TR2 have reached zero, the D counter steps to D3 of the cycle (Table I), in which the tax on the dollar portion is calculated. The ring counter T, made use of in this portion of the system is a 4-step unidirectional ring counter (or more steps if sales tax rises above present levels) which has the function of counting out the number of tax pulses (equivalent to one cent) in each dollar amount (in this machine, this is made a maximum of 4 cents). The ring counter T is preferably of the electronic type disclosed in the patent of W. J. Mahoney and N. Murthy, No. 3,235,748, issued February 15, 1966, which has a single active element, such as a 4-layer diode for each digit. The number of cents counted out are controlled by the gates A618, A619, A620 and A621, which are themselves controlled by flip-flop F1 11, F1 12, and ring counter T In the present case, it is desired first to issue the tax for between $4 and $5, and consulting the Connecticut schedule, this is seen to be 4 cents ($5.00, $4.72, $4.43 and $4.15). Because PF 11 is set, this enables gates A620 and A621. Because $5 is odd, gate A621 is enabled. Cycle D3 initiates a start pulse which is transmitted through the OR gate 066 and fires one-shot (delay 200 s.) multivibrator DMZ and through AND gate A627 sets flip-flop F1 13. This enables the applied oscillator timing pulses to pass through gate A626 and to be transmitted over the tax pulse line. These pulses are also counted up in the total cents counters TR1 and TR2 of the Total Register, now cleared of their previous contents. Simultaneously, these pulses are counted in T and when T reaches position No. 4, the gate A621 is enabled and an oscillator timing pulse passes therethrough to reset flip-flop F1 13. This pulse also resets T, to 0, counts down dollars counters TR3 and TR4 in the Total Register TR and shifts T to the 12 0 state. The delay multivibrator DMZ is tired, and the process starts again for the tax breaks between $4 and $3. The time gate A620 is enabled by T and three tax pulses are counted out.

This procedure is repeated until $2 is reached, when the flip-flop FFH is reset to 0, enabling gates A618 and A619. Under this condition, these tax breaks are selected by FFIZ for $1 and 0. The procedure is then the same as before. Finally, the total dollars counters TR3 and TR4 reach zero and this step in the cycle ends. The tax on the dollars part of the total is now stored in the total cents counters TR1 and TR2. This is done because the operation must be performed at 500 cycles per second to be fast enough (maximum tax calculation on dollars is 200 msec.). The tax pulses issue too fast for an electromechanical tax total counter to operate correctly, and, therefore, have to be stored electronically before transferring at a slower rate to the electromechanical counter.

The final step D4 in the D cycle is now to transfer the tax on the dollars from TR1 and TR2 into the tax total counter and into the Input Register IR at 40 c.p.s.

To summarize the procedure of tax calculation, the first operation is to transfer the sub-total which is in the Input Register, and being displayed on the visual indicator, to the Total Register. Then, the cents part of the sub-total is acted upon. Tax on the cents is calculated, and this information is stored in the mechanical cents tax counter. The original sub-total cents plus the tax on it is now stored in the cents part of the Input Register. Any carry passes directly into the units dollars of the Input Register. The tax on the dollars is now calculated. The tax information is stored in the cents counter of the Total Register. These counters had been previously cleared during the calculation of the tax on cents. The original sub-total dollars are now in the Input Register, and the tax on the dollars in the cents part of the Total Register. The total cents (tax on dollars) are now transferred to the Input Cents Register and the mechanical cents tax counter. The number in the Input Register is now the sub-total plus tax.

The sequence of operations performed by the machine to obtain the desired results may be called the Program. This is divided into separate cycles: (a) the Entry Cycle which occurs after each item quantity is entered, and (b) the Computer and Print Cycles which are performed at the end of a bill to compute tax, print tax and subtotal, and total, and to compute and print the change. The program is tabulated in a terse form in Table I for convenience when determining the operation of each step. The operation will be described in more detail later with reference to the operation flow chart in FIG. 12 and the main logical diagram of FIG. 13.

TABLE I Program (see FIGS. 12 and 1.?)

Cycle A-item entry:

A-l Rest position.

Start: Set by Clear or Print Complete and A3. Operation: Reset Total Carry FF. A-2 Start: Item Key Pulse or Amount Entry Key Pulse or B1. At: 5 kc. speed. Operation: Add from Input Register to Total Register. A3 Start: Input to Total Complete signal and A2. Operation:

(1) Print; (2) Set Input Register through previously enabled set gates; (3) Enable Total Carry Gate.

13 Cycle BSub-Total and wait for instruction:

BO Rest Position.

Start: Set by Clear, or B4 and Manual Tax signal or Special signal (where these options are provided). B-l Start: B and Sub-Total or Total Key at speed of kc. Operation: Start A Cycle-Add from Input Register to Total Register. (Note: If Total Key is depressed in Automatic Mode, Auto Tax FF is set). B-2 Start: B1 and Input to Total Complete signal at 5 kc.

Operation: Add from Total Register to Input Register. B3 Start: B2 and Total to Input Complete signal.

Operation: Print, Enable Mechanical Carry Gate.

Start: B3 and Print Complete signal.

Operation: Reset Mechanical Carry FF. Wait for Instruction.

Enables:

(a) Automatic Tax Cycle Gatef (b) Manual Tax Gate.*

(c) Special Item Gate.*

(d) Start C Cycle Gate.*

(e) Drawer Closure Gate.

(f) Transfer Gate.

* (If these options are provided).

Start: B4 and Auto Tax FF signal.

Operation: Start D Cycle (automatic tax).

Start: B4 and Manual Tax key signal.

Operation: Sets Manual Tax FF which inhibits Auto Tax Cycle Gate, enables Tax Counters, sets Oscillator for Bl to 20 cycles.

(Manual Tax is now entered through the manual entry keyboard via the A cycle. The Total key is then operated for the total.)

Start: Special key signal Operation: Sets Special FF which sets B0 and inhibits the Auto Tax Cycle Gate.

(The special item is then entered through the A register and Total key activated for the total).

Start: change key signal.

Operation: Start C register cycle (change cycle).

Start: Drawer Closure pulse.

Operation: Start C Register cycle.

Transfer Total signal.

Operation: Sets Transfer FF which starts C register cycle.

Cycle C-ehange calculation and enter totals in mechanical accumulators:

C-l Rest Position.

Start: Set by Clear signal. C2 Start:

B4 and Change key signal; B4 and Drawer Closure signal; B4 and Transfer signal.

At: 40 cycles per second.

Operation: Subtract Input and Total Registers.

Enter Total Register information into Mechanical Total Counters. Reset Manual Tax FF or Special FF.

C3 Start: C-2 and Total to Input Complete signal.

Operation: Enables Mechanical Carry Gates and Mechanical Dollars Total Counter- (a) Drawer Shut Gate;

(b) Drawer Open Gate;

(0) Transfer Clear Gate. (a) Start: C-3 and Draw Shut signal.

Operation: System Clear. (b) Start: C-3 and Drawer Open" signal.

Operation: Print. (c) Start: C-3 and Transfer FF signal.

Operation: System Clear. C-4 Start: C3 and Print Complete signal.

Operation: Enables End of Cycle Gate (will cause system clear if Drawer Shut signal occurs). Cycle D-Automatic Tax:

D0 Rest Position.

Start: Set by Clear signal or D-4 and Total Cent-s Complete signal. D1 Start: Auto Tax cycle gate signal at 5 kc.

speed. Operation: Add from Input to Total Register,

Reset Auto Tax FF. D2 Calculate Tax on Cents and Accumulate in Cents. Tax Mechanical Counter. Start: D1 and Input to Total Complete signal at speed of 500 c.p.s. Operation: Enable Mechanical Carry Gate and enable Tax Cents Counter. D3 Calculate Tax on Dollars and Store in Total Cents. Register. Start: D2 and Total Cents Complete signal at speed of 500 c.p.s. Operation: Reset Mechanical Carry FF. D4 Start: D-3 and Total Dollars Complete at speed of 40 =c.p.s. Operation:

Enable Dollar Tax Counter. Enable Cents Tax Counter. Enable Mechanical Carry Gate.

General operation (see FIGS. 1, 2 and 12) When an item key is depressed, the price of the item appears on the illuminated indicators above the keyboard, and is removed when a second item key is depressed and the second item price appears on the indicator. This is continued until all the items are entered in the Input Register, at which time the sub-total key is depressed. The total of all the item prices now appears on the indicator. Depressing the total bar opens the cash drawer and the sub-total price plus tax appears on the indicator.

During the entry of the items on the order, if it is desired to enter an amount for a special item for which there is no item key, this amount can be entered through the amount keyboard by depressing the appropriate keys.

If several of a given item are to be entered on an order, the appropriate numbered multiplier key is depressed and the item key in the item keyboard is held depressed until the illuminated multiplier keys count down to Zero, and the Mulitplier On light, which goes on when the multiplier key is depressed, counts down to zero when this light goes out. This will take no longer than about one second for a quantity of ten.

Special no tax or special tax items can be entered after the Sub-Total and prior to the Total by depressing the appropriate keys.

Normally, closing the cash drawer activates a reset of the electronic equipment to the initial condition which permits the next customers bill to be entered. For those cases where there is no cash dnawer or where it is purposely left open to speed up operations, a Total Transfer key is provided to reset when it is operated.

When change is to be computed, the amount tendered is entered on the amount keyboard after the total bar has been depressed. The change key is then depressed, and the amount of the change appears on the indicator.

If an associated printer is provided, all fingers appearing on illuminated indicator are printed by it plus a code identifying sub-totals, sub-total plus tax, special item, etc.

As each item is entered, its inventory counter is advanced so that a count can be kept of the number of units of each item dispensed. This same signal may be used to control automatic machines via a menu item memory (MIM), for example.

An overall cash total is maintained through a counter which is one of the mechanical counters. Optional tax totals or individual waiter totals can also be maintained via the mechanical counters. As previously stated, the item keys have provision for enabling changing of the legends applied thereto in case of a menu change and the unit price keyboard has provisions for quickly changing a group of prices on the individual item prices.

The complete circuits of the system of the invention including the optional features are shown in the overall schematic or logic diagram of FIGS. 13A to E in combination when arranged side by side in the manner shown in FIG. 14. As shown therein, the system includes a keyboard unit consisting of an item keyboard IK of up to 50 item keys or push buttons; an amount keyboard AK including a number of amount keys valued at 14; to $29.29 with an associated Manual Entry key; and a number of other functional keys including a Sub-Total, No-Sale, Manual Tax, Special, Total Transfer, Change and Clear.

The 50 item keys in the item keyboard IK are connected through individual buffer diodes BD to the adjustable or interchangeable price board APB which selects the item (or menu) prices. The price board APB, which may be a printed circuit wiring arrangement, comprises several columns of parallel wires representing respectively cents, ten cents, dollars and ten dollars. The adjustable arrangement of connections provided by pins or adjustable sliders on the price board APB connects these lines to the desired setting (output position) of the bidirectional ring counters IR1, 1R2, 1R3 and IR4 of the Input Register unit IR. Thus, when an item key is operated, the amount equivalent to the price of that item is entered directly into the item counters of the Input Register, which had been automatically cleared previously of input information in response to CLEAR signals generated by the CLEAR generator CG (FIG. 13E) under control of the CLEAR key through OR gate 062. The mamier in which the Item keys through the price board APB determine what price is set into theInpiit Register has been previously explained in connection with FIG. 4.

Each output position of the ring counters 1R1, 1R2, 1R3 and IR4 of the Input Register is connected to a cents, ten cent, dollars or ten dollar portions of the visual indicator VI, so that the output voltages cause the total item prices to appear on the indicator as the item is rung up.

A separate output is taken from each output line of the ring counters 1R1, IRZ, 1R3 and IR4 through individual bulfer diodes (not shown) to the print wheels (FIG. 13B) of the associated printer (not shown). When the printing of the item prices on each order is completed, a signal is sent back from the printer to start the transfer cycle which consists of counting the ring counters 1R1 to IR4 in reverse down to zero, and simultaneously sending pulses to the Sub-Total and Total counters. When the Item counter reaches zero, a transfer flip-flop device would be turned off-stopping the pulses, and the amount previously resting on the Item counter has now been added to both the Sub-Total and Total. Finally, the Item counter is cleared of the price information in the manner previously described ready for the next item to be entered.

Amounts for special items are entered directly from the amount keyboard AK by operating the amount keys thereof which are connected directly through the adjustable price board APB to the desired setting of the ring counters 1R1 to IR4 in the Input Register and starts the price and transfer cycle.

The bidirectional ring counters TR1 to TR4 (shown in FIG. 13C) constitute the Total Register TR. The manner It in which the price information is transferred to the Total Register from the Input Register has been previously described in connection with the simplified diagram of FIG. 3.

The multiplier unit MU (FIG. 13A) including the multiplier keys 2 to 10, the unidirectional ring counter RC1, the multivibrators MVl and MV2 and the associated gates are connected to the Input Register IR. Its optional use to provide multiplication in the system, if desired, has been previously described in connection with FIG. 5.

The mechanical accumulator unit MA, the selective oscillator SO, the selective gate sampler S65 and the automatic tax calculation circuit ATC are other units shown in the system of FIGS. 13A to 13E, and their operations have been previously described in connection with the block diagrams of FIGS. 7,- 8,- 10 and 11, respectively.

The system also includes four additional registers indicated by the boxes labeled A to D (FIGS. 13D and 1313), which are threeor four-position unidirectional electronic ring counters, such as disclosed in the aforementioned Mahoney and Murthy Patent No. 3,235,748. Their operation with the associated flip-flop devices and gating arrangements under control of the special functional keys to provide the item entry, computing and print cycles of the Program (Table I) will now be described.

The function of the A-Register or unidirectional ring counter is to enter item prices into the Input Register IR, either through the Item keys or the Amount keyboard AK. Assume that the A-Register is on position one, the rest position. The output AND gate A6101 is then onehalf enabled and the output AND gates A6102 and A6103 are disabled. If a start pulse now occurs via the 50 millisecond delay generator MVI being triggered by an Item key or Manual Entry key through OR gate 062, AND gate A6101 will have both halves enabled and a pulse passes into line A. Line A is connected to a Shift Register Driver SRD which acts to shift the A- Register to position two. At position two of the A-Register the following occurs: (1) one-half of A6102 is enabled; (2) the oscillator is gated for 5 kc. provided by one pulse output of the selective oscillator SO; and (3) an ADD Input to Total signal occurs causing the information in the Input Register IR to be transferred to the Total Register in the manner described in connection with FIG. 3. At the completion of this action, an Input to Total Complete signal occurs which enables the other half of A6102 to pass a signal to the A-line for shifting the A- Register via SRD to position three. At position three, the following occurs: (1) one-half of A6103 is enabled; (2) a Print Command Signal is given; (3) a Set Input Counter signal occurs; and (4) an Enable Total Carry Gate signal occurs. The Enable Total Carry Gate 6 signal passes any stored carry pulse from the Total Cents Register to the Total Dollars Register. The Set Input Counter signal acts to set the new item price or keyboard price into the Input Register in the manner previously described in connection with FIG. 4. The Print signal causes the printer to print the information in the Input Register (this means that the new information in the Input Register is printed each time). At the end of the print cycle, a Print Complete signal occurs which passes a signal through A6103 onto the A-line shifting the A-Register via SRD The A-Register is now shifted back to position one, as it is connected in a ring such that after the last position it returns to the first position. At position one of the A-Register A6101 is onehalf enabled. If only one item had been ordered, the A-Register cycle would end here. If the other multiplier keys had been used, the A-cycle would repeat once for each item ordered.

It has been shown that the A-Register adds the previous item price to the running total in the Total Register and inserts the new item price in the Input Register. At 

1. IN COMBINATION WITH A FIRST RING COUNTER OF BIDIRECTIONAL TYPE, HAVING CENTS, 10-CENT, DOLLARS AND 10-DOLLAR DECADE PORTIONS, FOR COUNTING AND STORING THEREIN PULSES IN NUMBER REPRESENTING INFORMATION ON THE TOTAL RUNNING PRICE BEFORE TAX, OR SUB-TOTAL PRICE, OF THE QUANTITY OF COMMODITY ITEMS, OR SERVICES, SOLD ON A SINGLE ORDER TO A CUSTOMER; A CIRCUIT FOR COMPUTING AND INDICATING THE TAX ON SAID SUB-TOTAL PRICE COMPRISING INDICATING MEANS INCLUDING MECHANICAL TAX COUNTER MEANS HAVING CENTS AND DOLLARS PORTIONS; A PLURALITY OF GATES EACH REPRESENTING A DIFFERENT TAX BREAK IN ACCORDANCE WITH SAID LAW, CONNECTED TO DIFFERENT OUTPUTS OF SAID COUNTER PORTIONS AND ADAPTED TO BE ENABLE THEREBY WHEN SAID FIRST COUNTER COUNTS, A SUM EQUAL TO THAT TAX BREAK; CONTROL MEANS CONTROLLED FROM THE OUTPUT OF SAID DOLLARS AND 10-DOLLARS COUNTER PORTIONS FOR SELECTING THE RANGE OF TAX BREAKS AND THE REPETITIVE CYCLES THEREOF UNDER SAID LAW APPLICABLE TO SAID SUBTOTAL PRICE; MEANS RESPONSIVE TO SIGNALS GENERATED BY SAID CIRCUIT IN DIFFERENT OPERATING CYCLES FOR CAUSING THE TAX ON THE CENTS AND DOLLARS PART OF SAID SUBTOTAL TO BE CALCULATED SEPARATELY IN THE FORM OF AN APPROPRIATE NUMBER OF PULSES OF ONE CENT VALUE EACH TRANSMITTED THROUGH ENABLED ONES OF SAID GATES SELECTED BY SAID CONTROL MEANS; AND MEANS FOR TRANSMITTING THE PULSE OUTPUTS OF ALL THE ENABLED GATES TO SAID INDICATING MEANS TO ACCUMULATE THE TAX INFORMATION THEREIN. 